How to charge a battery. An average car battery has a capacity of around 48 amp hours which means that, fully charged, it delivers 1 amp for 48 hours, 2 amps for 24 hours, 8 amps for 6 hours and so on.
This occurs when one of the soft, gel-filled discs between the vertebrae of the spine bulges or ruptures, compressing and/or irritating the sciatic nerve. Another common cause of sciatica is muscle spasm that compresses the sciatic nerve as it travels through the muscles.
Causes of Muscle Spasms. Muscle spasms in the back can often be caused by a twisting or strain on one of the back muscles, which in turn causes involuntary muscle contractions. Although this often occurs when tense, tight back muscles are present, it can happen in any circumstance.s a result of the contraction people often complain of having symptoms of either a locked back, or a knot in their back. Among the most common causes of muscle spasms in the back... 1  a sneeze or cough. 2  lifting heavy objects. 3  incorrect sitting posture. 4  muscle overuse, or injury. 5  dehydration.